Design Development of a Four-Story Strongback Braced Frame

Abstract:

Conventional braced frames tend to concentrate damage in one or a few stories during large earthquakes, indicative of “weak” or “soft” story behavior. To mitigate this behavior, several studies have proposed a modified braced frame, or “strongback”, that utilizes an essentially elastic vertical steel truss to impose a uniform drift distribution. While a subassemblage experimental test and past numerical studies have shown that the strongback system can successfully delay or prevent weak or soft story behavior, the dynamic behavior of this system has not been systematically assessed or evaluated. This study defines the design space for a four-story strongback system. The ability of the strongback to mitigate weak story behavior under a far-field suite of ground motions was assessed using the performance-based methodology in FEMA P695.

• Periodical: Key Engineering Materials (Volume 763)
• Pages: 1050-1057
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.763.1050
• Online since: February 2018
• Authors: Barbara Simpson*, Stephen Mahin
• Keywords: Buckling Restrained Braced Frame, Performance-Based Design, Strongback Braced Frames

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